Origin
I think Tyrannosaurus would be more accurate origin for Chigorasu than Allosaurus. Given that Chigorasu has short arms and a large head with strong jaws, it has more in common with Tyrannosaurus in terms of appearance than with Allosaurus. Allosaurus didn't have much of a bite force like Tyrannosaurus did and the arm length between the two species is different. Allosaurus has longer arms as seen here http://en.wikipedia.org/wiki/File:AMNH_Allosaurus.jpg and shorter on Tyrannosaurus. http://en.wikipedia.org/wiki/File:Tyrannosaurus_Rex_Holotype.jpg --Poke'fan07